Race-Bred Ignition Tech Now Powers the 2026 Jeep Grand Cherokee

A high-efficiency ignition system developed in racing engines is making its way into a mainstream Mopar vehicle, starting with the 2026 Jeep Grand Cherokee. 6-liter Pentastar V6, uses a pre-chamber ignition system known as Turbulent Jet Ignition (TJI) to burn fuel more completely and efficiently, without needing hybrid batteries.

The technology works by adding a small copper dome, about the size of a pencil eraser, to each cylinder head. Inside that dome are an extra fuel injector and spark plug. When activated, the pre-chamber fills with fuel, ignites it, and shoots multiple jets of flame through tiny holes into the main combustion chamber.

This ignites the air-fuel mixture faster and more thoroughly than a standard spark plug alone.

The system traces its roots to motorsport, where it was used in racing engines starting in the mid-2000s. It entered the Stellantis lineup through the Maserati MC20's twin-turbo V6 "Nettuno" engine. Mahle Powertrain, which worked with Ferrari on early versions of the technology, described it as a rapid technology accelerator.

In the Hurricane 4 Turbo, the system helps the engine produce 324 horsepower and 332 lb-ft of torque on regular 87-octane fuel, while achieving over 40 percent thermal efficiency. 0-liter engine, and 31 more horsepower and 72 more lb-ft of torque than the Pentastar V6. The engine also runs cooler, which could improve durability.

Pre-chamber ignition is not unique to Stellantis. BMW's latest M3 straight-six also uses a version to meet stricter emissions rules. The technology allows automakers to keep combustion engines powerful while cutting fuel use and emissions, without adding heavy hybrid systems. The Hurricane 4 is the first modern mass-market application of this technology, and future Mopar models may adopt it as well.